You like fantasy world with fantasy beasts, knights, magic and stuff?
You should give this a watch. Though the difference are Re:Zero hasn't got a skillful MC and the plot is more deeply psychological than the world of SAO.

Actually quite similar in construction, both have a similar premise - that a protagonist get trapped in a fantasy world and gains a special ability. Onward, both protagonist become surrounded by the opposite gender but have their sight on only one girl. Furthermore, both anime have a fair amount of action and some deep psychological moments.

SAO differs with a primarily romance focus to it while Re:Zero goes about dealing with darker themes and the psychological aspect to it.

Compared to Sword Art Online, Re: Zero is much darker at times in terms of gore and overall subject matter. However, both shows are set in beautifully created fantasy worlds that are filled with unique and memorable characters that you can't help but fall in love with. The action sequences will keep you engaged throughout and the more mature themes will get you thinking about life on a deeper level. If you enjoy fantasy, action, with some romance thrown in as well, then definitely give this show some screen time.

Delivers where Sword Art Online does not; Re:Zero is a personal journey dealing with death anxiety, so much so that the protagonist sometimes descends into madness. It more accurately captures a 'RPG' dynamic, with respawning actually being a thing, which actually makes the series even more devastating. Also features a more reasonable 'levelling-up' of the main character meaning there is a genuine struggle.

Both of these anime are very well known, and represent a teenage boy stuck in an rpg game like world. Personally i prefer rezero quite a bit, because of its darker tone, and mysterious aspect, but i really like both of these anime.

In sao, a boy enters a virtual reality game alongside many others, and finds that they cannot leave, and the story follows from there, as he and many other gamers try to beat the game as it's there only way of getting out (and avoid dying ingame, which will lead to their real bodies dying)

In rezero, a boy is
mysteriously transported to an rpg video game like world, but there's an interesting addition to this series where he has the ability to return to previous times after his death as a form of retry. This leads to him going through many traumatic deaths, as he tries to save the girl he has fallen for, and the world alongside it.read more

Main charecter summoned to a fantasy world where magic and other things exists, but the problem is he stays as a human, which dosent have any kind of power (sword skills,magic,etc) BUT he has a unkown power: when he dies, he can turn back to a specific location and time, which will change after some time.
he tries to understand the meaning of this change and the same time he tries to save many people as posibble, especially the ones he loves the most.
its little bit complicated to describe so just
go to the main page that describes the anime and read the description.read more